1. Field of the Invention
The present invention relates to a motorized electric toothbrush having an automatic mode of operation.
2. Background Art
Use of motorized electric toothbrushes used as an aid in cleansing teeth is well known. Typically these toothbrushes employ rotating, reciprocating, or oscillating motion, or a combination thereof, to effectuate the cleaning process.
A feature commonly found on these toothbrushes is an on/off switch located on or near the handle portion of the toothbrush. The primary feature of such a switch is that it remains either in the “on” position or the “off” position until the user manually changes it. With such a switch, the user has a limited number of choices. The toothbrush motor can be engaged prior to the brush head being placed in the mouth, or the user can wait until the brush head is placed within the mouth before engaging the motor. Both of these choices may have undesirable consequences. When the user engages the motor prior to placing the brush head in the mouth, the rapid movement of brush head may cause the toothpaste to be shaken off the bristles. Conversely, if the user waits until the brush head is inside the mouth, and in particular in contact with the teeth, it may be difficult to engage the switch, depending on its position relative to the user's hand.
Another feature found on some motorized electric toothbrushes is a removable brush head section. This allows the brush head section to be replaced when the bristles become worn, and also allows the same toothbrush to be shared by multiple users. Typically, a removable brush head section attaches to the toothbrush handle and contains linkages to transfer mechanical power from the motor to a bristle head. Different types of attachments and linkages are known in the art, with particular mechanisms chosen to achieve particular results. For example, U.S. Pat. No. 6,308,359 issued to Fritsch et al. on Oct. 30, 2001 describes a motorized electric toothbrush having a removable brush section with an attachment mechanism intended to reduce noise and vibrations. Another example is found in U.S. Pat. No. 5,836,030 issued to Hazeu et al. on Nov. 17, 1998. Hazeu et al. describes a motorized electric toothbrush having a removable brush attachment with linkages designed to induce specific bristle motions. None of these designs includes an automatic mode of operation that provides for motorized operation only when the toothbrush is being used by an operator.
Accordingly, it is desirable to provide an improved motorized electric toothbrush that overcomes the above referenced shortcomings of prior art toothbrushes, by providing an automatic mode of operation in which the motor engages when the toothbrush is being used by an operator.